I don't know if you habitually use oil when drilling metal now, but you should certainly use a lubricant of some sort. It saves the bit, lets the drilling go a little easier and produces a really nice curl. That's how you know you are getting good cutting; when the metal curls out in long spirals instead of coming out in thousands of little chips.

I used oil for this for a long time. Then I read a tip somewhere, (I don't remember where, but this tip is not original with me), that antifreeze would do as good a job.

I think it does a better job!

It lubricates the bit and produces an excellent curl; every bit as good as oil.

It is a lot less messy. It doesn't collect in a sticky, oily, metallic mess on the drill press table or on the floor, and it is a lot easier to clean up, especially because it is soluble in water.

It's cheaper. A gallon will last for years.

I use a French's mustard squeeze bottle I got from my neighborhood deli to apply it. Just squeeze a little stream onto the bit and keep doing it by raising the bit and squirting a little more into the cavity formed by the drill bit.

Works great!